NodeJS http.request end processing before data processes - json

Question

Can some explain why the the http.request end function is running before any data is actually retrieved? And how would I debug this any further? Should I be checking an http status?
This is going to work with Google Home app, but I took that code out and getting same error running locally. The http.request is from what a teacher provided in a class.
You can paste: people/?search=Luke%20Skywalker
into http://swapi.com (SW = StarWars API) to see the expected result.
'use strict';
/*eslint no-undef: "error"*/
/*eslint-env node*/
/*eslint-disable no-console */
let http = require('http');
let starWarsAPI = `www.swapi.co`;
//function to get details of the Star Wars Characters
//exports.handler = function(event, context, callback) {
//console.log("event=" + JSON.stringify(event));
//console.log("context=" + JSON.stringify(context));
//let characterName = event.result.parameters.StarWarsCharacter;
let characterName = "Luke Skywalker";
console.log("**** characterName=" + characterName);
let options = searchPeopleRequestOptions(characterName);
console.log("options=" + JSON.stringify(options));
makeRequest(options, function( data, error) {
console.log(" Processing data.results");
let person = data.results[0];
if (person) {
let height = person.height;
let mass = person.mass;
let response = person.name + " is " + height + " centimeters tall, weighs " + mass + " kilograms";
console.log("**** response=" + response);
//callback(null, {"speech": response});
}
else {
console.log ("No person found");
//callback(null, {"speech": "I'm not sure that character exists!"});
}
});
//};
console.log("The end");
//create a function to read first and last names from the API.
function searchPeopleRequestOptions(argCharacterName) {
var pathValue = `/api/people/?search=`+
encodeURIComponent(argCharacterName);
return {
host: starWarsAPI,
path: pathValue
};
}
function makeRequest(options, callback) {
var responseString = "";
var request = http.request(options,
function(response) {
response.on('data', function(data) {
responseString += data;
console.log("responseString=" + responseString);
});
response.on('end', function() {
console.log("end: responseString=" + responseString);
// dies on next line because responseString is empty
var responseJSON = JSON.parse(responseString);
callback(responseJSON, null);
});
response.on('error', function (error) {
console.log('\n Error received: ' + error);
});
});
request.end();
}
This is what I see when I run it:
E:\GitHub\NealWalters\GoogleHomeTest
λ node indexTest.js
**** characterName=Luke Skywalker
options={"host":"www.swapi.co","path":"/api/people/?search=Luke%20Skywalker"}
The end
end: responseString=
undefined:1
I'm not sure what's writing out the "undefined: 1" line.

Answer 1

If you look at the server's response status code, it will be 301: Moved Permanently.
And value of location field of response is:
https://swapi.co/api/people/?search=Luke%20Skywalker
instead
http://swapi.co/api/people/?search=Luke%20Skywalker
As we can see, the protocol changed from http to https.
The problem is that the http client supplied with the node.js does not support redirection for permanently changed URL.
So, you can use https module instead http (just change the require('https')).
Or use packages that support redirection. For example axios or request.